docs: def hazard_items(dic, mesh, *extras, **kw):
      """
      :param dic: dictionary of arrays of the same shape
      :param mesh: a mesh array with lon, lat fields of the same length
      :param extras: optional triples (field, dtype, values)
      :param kw: dictionary of parameters (like investigation_time)
      :returns: a list of pairs (key, value) suitable for storage in .npz format
      """
      for item in kw.items():
          yield item
      arr = dic[next(iter(dic))]
      dtlist = [(str(field), arr.dtype) for field in sorted(dic)]
      for field, dtype, values in extras:
          dtlist.append((str(field), dtype))
      array = numpy.zeros(arr.shape, dtlist)
      for field in dic:
          array[field] = dic[field]
      for field, dtype, values in extras:
          array[field] = values
      yield 'all', util.compose_arrays(mesh, array)